This invention relates to television systems and is particularly concerned with means for enhancing the utility of the standard television receiver.
Numerous systems and techniques have been proposed for utilizing the display and monitoring capabilities of the standard television broadcast receiver, in addition to its well-known function of receiving commercial and public service television programs. The enhancement of the utility of the television receiver is attractive in the many potential benefits offered. The television receiver is inherently capable of conveying complex video and audio information via a single coaxial conductor which may be attached to a dedicated cable system and/or to a separate antenna for receiving over-the-air broadcasts. A major attraction of the television receiver is its ubiquity; there are currently more than 90 million television receivers in operation in the United States alone, with the number constantly increasing.
Systems and techniques proposed for increasing the utility of the television receiver, represented by various examples of letters patent, include the use of television receivers with information banks and intercom systems, for entrance monitoring, and in conjunction with telephone systems.
For example, Great Britain Pat. No. 2 002 995A Klein et al, discloses a method and apparatus that provides two modes of operation with respect to a television set, according to applicant's understanding. A first mode provides for communication with other subscribers to a screen text information service (assumed to be Teletext, Viewdata, or the like) by means of a conventional loudspeaker phone separate from the television receiver. A second mode provides for connecting a television set with the screen test information bank. It is understood that subscribers to the service can contact and instruct the service as to what type of text information is desired by means of a remote control key pad, and receive programmed service announcements through the television loud speaker. A subscriber line of a subscriber operated telephone network can be switched over selectively to a telephone handset, or to a modulator-demodulator. The modem effects the line termination of a subscriber line for connection to a remote control device located in the television set. In one embodiment, number-selection characteristics signals are produced using the digit keys on a keyboard of the remote control device, or alternately, dialing is accomplished automatically by the switching means of the telephone by actuating a start key on the keyboard. In both cases, the interface between the telephone line and the television receiver with its separate remote control is as best understood, by means of a separate handset telephone.
U.S. Pat. No. 3,668,312 to Yamamoto et al discloses a "television telephone" system having means for sending back an indication signal from an information receiving party of a television telephone system to an information-transmitting party of the system. A light pen is used which detects the light of the raster of the transmitted information picture so as to indicate a command of the receiving party to the information transmitting party. The system is said to be applicable to existing television telephone subscribers by a minor modification and allegedly improves tthe utility of the "television telephone" system for information exchanging.
Shaver et al in U.S. Pat. No. 3,816,662 discloses a combination telephone and video communication system for selectively enabling, from a given location in which a video terminal is provided, another video terminal at a desired one of a plurality of remote locations. Specifically, the invention is concerned with an enabling arrangement in conjunction with intercom and door-answering systems for apartment or the like buildings. The purpose is to make it possible for the tenant in an apartment to converse with and to see a visitor calling from an entrance of the building.
In Stetten U.S. Pat. No. 3,746,780--means are disclosed which permit individual ones of many television receivers to display on their screens individually adapted, and different, displays from a commonly received, sequential video television signal. The telephone is used to dial a television display system which has been subscribed to which provides information such as weather forecasts. The selection for display at particular display devices is on the basis of information data incorporated within the video signals. Video recorders are described as being adapted to record selected portions of commercial television-type video signals for maintaining the image displayed on associated television receivers.
Tanner U.S. Pat. No. 3,492,418--discloses a signal transmission system using DC control signals to selectively operate a television receiver as a monitor and to control an intercom system. The system is said to include a camera with one section of an audio intercom nearby. A television receiver and another section of the intercom are located at some distance from the camera. A switch near the receiver has a first position to connect the antenna to the receiver and to simultaneously turn off the camera and the intercom. A second section disconnects the antenna, connects the camera to the receiver, and turns the camera and intercom off. A cable connecting the camera to the receiver has a single shielded conductor for transmission of the camera signal, the audio intercom signal and the power on-off control.
However, despite these and many other proposals for the greater utilization of the capabilities of the television receiver, innumerable possibilities for greater utilization of the system remain as yet untapped.